I am a school bus driver in Saint Johns County, northeast Florida. I play music all day on my bus for all three flights 2x day k-12grades with an assortment of iPods I load with music from a 4 TB external HD or from a pair of MacBook pros.
I have been using an ANKER SoundCore2 for years to do this but lately I have issues with some jerks who refuse to shut of their Bluetooth while on the bus so their god-awful music over-rides what i have playing and this is done on purpose just because they can, though it is a referrable offense. If they collect 3 they can be removed from the bus for an indeterminate time but I have no means to track down the offender.
What I need because i can afford it is a non-Bluetooth chargeable speaker with superior sound qualities that I enjoy with the SoundCore 2, cord connectable only.
Any suggestions? Every time I do a search all I am shown is Bluetooth / hard wired as if there is no alternative. Even passing cars running Bluetooth interrupt what I am playing via cable connection.
What is the best portable NON BLUETOOTH speaker??
Have you considered the soundcore motion+? I believe it has a 3.5mm aux in port that you could connect to your device.
I think also there are a couple others that I will try to find…
Perhaps a flare or maybe the motion q. I’ll post an edit to this reply either way.
Edit for links to flare and motion+
Here are two links to reviews for aux in port capable soundcore speakers, the motion+ would be most similar to what you currently have:
Technologyman review - motion +
You could use all speakers with an AUX input if your phone got an AUX output.
Be careful :
Some modern speakers don’t have this input any more and modern phones don’t have that output anymore.
As @TheSnarkyOne mentioned I can recommend that motion +
(heavy and sturdy) I will not drop down so easily when bus driving 
)
I have one since some time, great an perfect sound. and its supported by the spoundcore app.
Today its a little bit difficult for bus drivers here in München,
heavy snow falls. 
Faraday cage?
Bluetooth is 2.4Ghz, wavelength 122cm.
So if you place the speaker in metal, say tin foil, or metallic ceramic, with just small holes over the speakers then it will reflect the radio signals. Not many small holes just one small hole.
Feed wires aux and usb power through. Use shielded high quality wires.
It is hard to make a good metal cover. Also just bags or plastic bottles of water packed around do a decent job. The shielding pointing to the passengers nearest matters more so point the holes for sound away from the nearest people.
If it works then get the science class to make a poster to display as then they can begin to learn.
Do you really think there will be any good sound after wrapping the speaker in metallic foil?
So long as the hole is significantly less than 122cm then little can get through the box you use can be any size.
Plastic water bottles do similar.
Sound is much lower frequency and will tend to make the box transmit sound.
Try yourself?
Works
If doing this for real I’d stick some round plastic small cups over where you want the sound out, then wrap round 3 times with foil, the key seems to be COMPLETELY wrap including covering the ends, then cut and pull out the cups to leave the holes.
The holes let the signal in but probably multiple layers of foil will mean only the very nearest signal get through so you know which kid is the prankster.
Voilà a non Bluetooth speaker costing a few pennies and a few minutes effort, less effort than buying another speaker.
For a solid portable non-bluetooth speaker, check out the Anker Soundcore mini. It’s small but packs a punch with great sound quality, plus it has an AUX input for non-bluetooth connections. Another good pick is the JBL GO 2. It’s durable, sounds fantastic, and also has an AUX input. Both are awesome choices if you’re looking for reliable, portable speakers without bluetooth. And these can also be used when you’re using an whatsapp.